replace < String < JavaScript

The replace() of a String returns a new string with the specified string replaced. The pattern can be a string or a RegExp, and the replacement can be a string or a function called for each match. If the pattern is a string, only the first occurrence will be replaced. The original string is left unchanged.

    
    const paragraph = "I think Ruth's dog is cuter than your dog.";

    const paragraphReplace = paragraph.replace("Ruth", "Cindy");

    console.log(paragraphReplace);
    // "I think Cindy's dog is cuter than your dog."


    // example use a regex instead of a string
    const regex = /Dog/i;

    const paragraphReplaceRegex = paragraph.replace(regex, 'ferret');

    console.log(paragraphReplaceRegex);
    // "I think Ruth's ferret is cuter than your dog!"


    // example replacing all instances of word
    const text = "Java is awesome. Java is fun."

    const pattern = /Java/g;   // g is global for regex
    const textReplace = text.replace(pattern, "JavaScript");
    console.log(textReplace);
    // "JavaScript is awesome. JavaScript is fun."